Phytotoxicity and Efficacy of Fascination (6-Benzyl Adenine + Gibberellic Acid) for Enhanced Branching of Gaura (Gaura lindheimeri Siskiyou Pink ) By Heiner Lieth, Director Linda Dodge Shannon Still Lea Ragaini Ron Lane Jackie Fortunko Project: Interregional Research Project #4 Project Number 23227A - July 29, 2004 Acknowledgements: Ahmet Gulcu Donors/Supporters: CDFA Minor Crops Research Grant, Project 2: Enhancement of the Western Region IR-4 Program to Address California Needs Green Leaf Perennials, Lancaster, PA UC Davis Environmental Horticulture IR4 Center Department of Environmental Horticulture University of California One Shields Ave. Davis, CA 95616 http://envhort.ucdavis.edu/ir4
1. INVESTIGATOR (Name, Address, Phone#): Dr. Heiner Lieth Department of Environmental Horticulture University of California One Shields Ave. Davis, CA 95616 Ph 530-752-7198 FAX 530-752-1819 Email: jhlieth@ucdavis.edu IR-4 ORNAMENTAL DATA REPORTING FORM (Please type or print) LOCATION OF TRIAL: TRIAL TYPE:(check one) FIELD CONTAINER X GREENHOUSE INTERIORSCAPE 2. PESTICIDE: COMMON NAME: 6-Benzyl Adenine + Gibberellic Acid A 4 A 7 FORMULATION: 1.8% + 1.8% (w/w) BATCH NO.: EPA REG. NO. 27135 PRODUCT: Fascination MFG: Valent 3. USE INFORMATION: COMMON NAME SCIENTIFIC NAME PLANT: Gaura Gaura lindheimeri Siskiyou Pink REASON: enhanced branching of potted crops SOIL TYPE OR TYPE OF POTTING MIX: UC Mix % SAND 35 % SILT % CLAY % OM 65 % ph 6.5 SEEDING DATE EMERGENCE DATE TRANSPLANTING DATE 4/18/04 PLANT OR POT SPACING 6 ROW SPACING 6 POT SIZE 6-inch PLOT SIZE 50 sq. ft. EXPERIMENTAL DESIGN randomized complete block NO.OF REPS 9 (3 blocks) 4. APPLICATION PARAMETERS: TYPE OF APPLICATION: foliar NO. OF APPLICATIONS 2 APPLICATION TYPE manual spray bottle NOZZLE TYPE/SIZE NOZZLE PRESSURE DELIVERY RATE CALIBRATION DATE(S) 5. APPLICATION SUMMARY: APPL.DATE RATES (ppm)* GROWTH STAGE 6/17/04 0, 125 (0.5X), 250 (1X), 500 (2X) 8 weeks post-transplant 7/08/04 0, 125 (0.5X), 250 (1X), 500 (2X) 11 weeks post-transplant *Be sure to provide units 2
IR-4 ORNAMENTAL DATA REPORTING FORM (Please type or print) 6. RAINFALL/IRRIGATION RECORDS: INCLUDE RAINFALL/IRRIGATION INFORMATION (printouts, IR-4 forms, etc.) Plants were watered as needed (at least once daily) with half-strength Hoagland s solution 7. OTHER PESTICIDES, FERTILIZER, LIME AND ADJUVANTS USED: PRODUCT Orthene + Sanmite AMOUNT DATE 6/23/04 PRODUCT Orthene + Heritage AMOUNT DATE 6/30/04 PRODUCT Talstar F AMOUNT DATE 7/08/04 PRODUCT Pylon AMOUNT DATE 7/21/04 8. NARRATIVE SUMMARY OF METHODS AND RESULTS: (Use more pages if needed) Materials and Methods Plant Material and Culture. Young plants of Gaura lindheimeri Siskiyou Pink were received from Yoder Bros. on 4/12/04. These were transplanted to 4-inch pots containing UC Mix on 4/18/04 and maintained in a greenhouse under natural day length for 8 weeks until the experiment began on June 17, 2004. Prior to the experiment, the plants were repotted into 6-inch pots containing UC Mix. For the experiment, the plants were transferred to a greenhouse under natural day length with day/night temperatures of 82 F/65 F (28 C/18 C) (Figure 1). The plants were watered as needed (at least once daily) during the 6-week experiment with half-strength Hoagland s solution. Applications of pesticides as part of a normal pest management program were made as needed (see No. 7 above). Experimental Procedure. Thirty-six plants were randomly chosen and individually tagged for treatment with 0, 125 ppm (0.5X), 250 ppm (1X) or 500 ppm (2X) Fascination with 9 replicates per treatment. These dosages were prescribed in an IR4 Fascination protocol dated 6/04 (Appendix A). The plants received the first of two foliar spray applications of the designated treatments on June 17, 2004 using manual spray bottles to spray leaves to runoff. The second application was made 21 days later on July 8, 2004. The plants were arranged in a randomized complete block design with 3 blocks and 3 treatment replicates per block. Phytotoxicity and efficacy measurements were taken at day 0 (June 17, 2004), day 21 (July 8, 2004) and day 42 (July 29, 2004). Phytotoxicity evaluations were based on a numerical rating scale of 0 (no injury) to 10 (complete kill) (Table 1). Efficacy measurements consisted of overall plant height (cm) and width (cm). Statistical Analysis. The data were analyzed using Proc GLM of the Statistical Analysis System (SAS). The phytotoxicity and change in mean value from the starting plant height and width were analyzed for significant differences using t-tests. Results Phytotoxicity Index. Fascination at all application rates had no effect on phytotoxicity index for G. lindheimeri Siskiyou Pink as compared to control (0 ppm) (Figure 2, Appendix B). Efficacy. G. lindheimeri Siskiyou Pink plants treated with Fascination at rates of 125 and 500 ppm exhibited greater increases in height than those treated with 250 ppm or controls (0 ppm) at 3 weeks (Figures 3 and 3a, Table 2). At 6 weeks, Fascination at all rates caused greater height increases for G. lindheimeri Siskiyou Pink than the control (0 ppm). G. lindheimeri Siskiyou Pink plants treated with Fascination at 500 ppm showed greater increasse in width than those treated with the 250, 125 and 0 ppm rates at 3 weeks (Figure 4, Table 2). At 6 weeks, Fascination at a rate of 125 ppm caused greater increases in width for plants of G. lindheimeri Siskiyou Pink than the control (0 ppm). The other treatments were not significantly different. 3
Discussion Phytotoxicity. Fascination at all rates tested caused no phytotoxicity symptoms on G. lindheimeri Siskiyou Pink. Efficacy. Foliar application of Fascination did affect the height and width of G. lindheimeri Siskiyou Pink as all application rates had greater increases in height than the control at 6 weeks. The results at 3 weeks were not as conclusive but were still significant. The 125 and 500 ppm application rates were significantly more effective for increasing height than the 250 ppm (recommended) rate. We have no explanation for this aberration. Increase in plant width for G. lindheimeri Siskiyou Pink was significantly greater at the 500 ppm application rate (double the recommended rate) than all other treatments and control. At week 6, however, only those plants treated with 125 ppm Fascination (half the recommended rate) showed significantly greater increases in width than the control plants. The pictures presented (Figure 3a) suggest that Fascination may have an interesting production effect. We observed that the higher the Fascination application rate, the more rapidly the plants reached flowering. What is not evident in the pictures (and was also not measured) is that the plants in the 500 ppm treatment had already flowered, while the control plants were just reaching full bloom. Thus we recommend that for this crop, Fascination be evaluated for its potential to speed up the production cycle and consequently save the grower substantial amounts of money. This is just as important as optimizing the shape of the plant. 9. GOOD RESEARCH PRACTICE STATEMENT: I acknowledge that I have read and followed the IR-4 Research protocol and completed this trial following good agricultural practice, or reported any deviations (note any changes from authorized protocol in narrative). SIGNATURE PRINCIPAL INVESTIGATOR DATE 4
Table 1. Numerical plant damage rating scale used for phytotoxicity determinations. Rating Description of plant damage 0 No damage 1 No visible damage but unintended (non-permanent) impact 2 Slight leaf/tissue damage (curling leaves, necrosis, etc.) 3 Marginal chlorosis on some leaves (damage on up to 10% of plant) 4 10% 20% of plant damaged 5 Significant damage to much of plant (30% - 40%) 6 40% 60% of plant damaged 7 Chlorosis or necrosis on most of plant (60% - 70%) 8 Abscised leaves, branch dieback 9 Tissue severely damaged (80% - 100% of plant) 10 Complete kill Air Temperature - Greenhouse 180 90 Temperature (F) 85 80 75 70 65 60 55 50 6/12/2004 6/19/2004 6/26/2004 7/3/2004 7/10/2004 7/17/2004 7/24/2004 7/31/2004 Figure 1. Greenhouse temperatures during the experiment to evaluate the effects of Fascination on Gaura lindheimeri Siskiyou Pink. 5
Phytotoxicity index 10 9 8 7 6 5 4 3 2 1 0 Control 125 ppm (0.5X) 250 ppm (1X) 500 ppm (2X) 0 3 6 Duration of experiment (weeks) Figure 2. Phytotoxicity Index for Gaura lindheimeri Siskiyou Pink treated with 0, 125, 250 or 500 ppm Fascination. SE bars shown. n=9. See Table 1 for explanation of values. 6
Plant height (cm) 60 55 50 45 40 35 30 25 20 15 10 5 0 Control 125 ppm (0.5X) 250 ppm (1X) 500 ppm (2X) 0 3 6 Duration of experiment (weeks) Figure 3. Plant height of Gaura lindheimeri Siskiyou Pink treated with 0, 125, 250 or 500 ppm Fascination. SE bars shown. n=9. Table 2. Average increase (cm) of height and width for plants in the control and Fascination treatments for Gaura lindheimeri Siskiyou Pink. Different letters within a column indicate significant differences between different treatments (P < 0.05). Means ± SE (n=9). Height increase (cm) Width increase (cm) over 3 weeks over 6 weeks over 3 weeks over 6 weeks Control 18.89 ± 1.90 b 15.33 ± 4.07 b 31.22 ± 2.00 b 63.44 ± 2.19 b 125 ppm 30.33 ± 2.05 a 28.44 ± 3.34 a 31.11 ± 2.15 b 99.78 ± 16.98 a 250 ppm 21.11 ± 1.76 b 29.56 ± 3.81 a 37.22 ± 2.76 b 76.11 ± 6.69 ab 500 ppm 28.11 ± 1.18 a 33.22 ± 1.95 a 44.67 ± 1.79 a 83.33 ± 3.69 ab 7
Control 125 ppm 250 ppm 500 ppm Block A Control 125 ppm 250 ppm 500 ppm Block B Control 125 ppm 250 ppm 500 ppm Block C Figure 3a. Gaura lindheimeri Siskiyou Pink plants 6 weeks after 2 foliar applications of 0, 125, 250 or 500 ppm Fascination (Week 0 and Week 3). 8
Plant width (cm) 140 130 120 110 100 90 80 70 60 50 40 30 20 10 0 Control 125 ppm (0.5X) 250 ppm (1X) 500 ppm (2X) 0 3 6 Duration of experiment (weeks) Figure 4. Plant width of Gaura lindheimeri Siskiyou Pink treated with 0, 125, 250 or 500 ppm Fascination. SE bars shown. n=9. 9
Appendix A: GROWTH ENHANCEMENT OF ORNAMENTAL PLANTS WITH FOLIAR APPLICATIONS OF 6-BENZYL ADENINE + GIBBERELLIC ACID (FASCINATION) Date: 6/04 Ornamental Protocol Number: 670 General label directions: Refer to product label or Technical Bulletin. Research program: Pest(s)/Plants Plants other than labeled species. Pesticide (common name and trade name): Refer to treatment list shown below. For label, material & if needed, spray surfactant contact: Valent USA, Joe Chamberlin, 770-985-0303, jcham@valent.com Plot size (must be adequate to reflect actual use condition) Replicates Minimum of 4 Treatment Units Controls (untreated controls to be included in all experiments) Application: FASCINATION Dosages - 1/2x 125 ppm or 0.125 pt/5 gal. 1x 250 ppm or 0.25 pt/5 gal. 2x 500 ppm or 0.5 pt/5 gal. Active Ingredient: 6-benzyl adenine + gibberellic acid (FASCINATION). Volume - Minimum of 100 gal/a. Timing - 2 Applications, 21 day spray interval. Record number of branches and length, then increased branching, increased extension and crop safety at 7, 14, 21 (then 2 nd appl.), 28 and 42 DAT. Reports: Method of application: Treatments should be applied according to product label instructions. application equipment consistent with conventional commercial equipment. Report completely on experimental design and method of application. Report plant size height x width before treatment and throughout the experiment. Weather Maintain temperature and precipitation (including irrigation) data. Soil type Identify soil type used in experimental area. Product When submitting data, include EPA registration number of product used. Efficacy Data should include percent control as well as an indication that infestation was light, heavy, etc. Record all application and evaluation dates. Phytotoxicity Record phytotoxicity data at all rates. Use a 0-10 scale. 0 = No Phytotoxicity 10 = complete kill. Please direct questions to: Dr. Robert M. Herrick, IR-4 Project, 681 US Highway #1 South, North Brunswick, NJ Phone: (732) 932-9575, Ext. 629. 10
Appendix B: PHYTOTOXICITY REPORT FORM Gaura Data Phyto Phyto Phyto Rate Rate Rate Fascination Treatment Block Rep 6/17/04 7/8/04 7/29/04 Control A 1 0 0 0 Control A 2 0 0 1 Control A 3 0 0 0 Control B 1 0 2 3 Control B 2 0 0 0 Control B 3 1 0 0 Control C 1 1 0 0 Control C 2 1 3 1 Control C 3 1 1 2 Control Mean 0.44 0.67 0.78 Control Std Dev 0.53 1.12 1.09 125 ppm A 1 1 1 2 125 ppm A 2 0 0 0 125 ppm A 3 1 1 1 125 ppm B 1 1 0 0 125 ppm B 2 0 0 2 125 ppm B 3 1 0 1 125 ppm C 1 1 0 1 125 ppm C 2 0 0 1 125 ppm C 3 1 1 1 125 ppm Mean 0.67 0.33 1.00 125 ppm Std Dev 0.50 0.50 0.71 250 ppm A 1 1 2 0 250 ppm A 2 0 0 2 250 ppm A 3 1 1 1 250 ppm B 1 0 3 5 250 ppm B 2 0 1 1 250 ppm B 3 0 1 1 250 ppm C 1 0 0 0 250 ppm C 2 0 1 2 250 ppm C 3 1 1 2 250 ppm Mean 0.33 1.11 1.56 250 ppm Std Dev 0.50 0.93 1.51 500 ppm A 1 0 2 2 500 ppm A 2 0 0 1 500 ppm A 3 0 0 2 500 ppm B 1 1 0 1 500 ppm B 2 0 0 1 500 ppm B 3 0 0 1 500 ppm C 1 0 0 2 500 ppm C 2 0 0 1 500 ppm C 3 0 0 2 500 ppm Mean 0.11 0.22 1.44 500 ppm Std Dev 0.33 0.67 0.53 NOTE: DEFINE MEASUREMENT OF PHYTOTOXICITY, OR INDEX OF INJURY (0=NO INJURY, 10=COMPLETE KILL) (See Table 1) 11
Appendix C: EFFICACY REPORT FORM Gaura Data Plant Plant Plant Plant Plant Plant Height Height Height Width Width Width Fascination (cm) (cm) (cm) (cm) (cm) (cm) Treatment Block Rep 6/17/04 7/8/04 7/29/04 6/17/04 7/8/04 7/29/04 Control A 1 19 48 42 16 47 92 Control A 2 20 39 44 19.25 51 78 Control A 3 28.5 47 22 24.75 47 80 Control B 1 22 36 20 18.5 57 77.5 Control B 2 28 41.5 41.5 19.75 52 81.5 Control B 3 18 45.5 36 15.25 46.5 82.5 Control C 1 25.5 34.5 42 20 56.5 86.5 Control C 2 24 37 39 28.25 44.25 77.5 Control C 3 23.5 50 61 20.75 62 96 Control Mean 23.17 42.06 38.61 20.28 51.47 83.50 Control Std Dev 3.77 5.74 12.20 4.06 5.96 6.68 125 ppm A 1 21 54 49 16.75 43 123.5 125 ppm A 2 19.5 45 56 14.75 43.5 246 125 ppm A 3 16 52 36 15.5 50.5 83 125 ppm B 1 24 54 40 15.25 48.25 100 125 ppm B 2 15 41 47.5 16 45 116 125 ppm B 3 27 40 30 14.5 55.5 80.5 125 ppm C 1 12.5 42 43 17 41 104.5 125 ppm C 2 16.5 50.5 54 15.75 39.75 104 125 ppm C 3 7.5 55 61 18.75 58 85 125 ppm Mean 17.67 48.17 46.28 16.03 47.17 115.83 125 ppm Std Dev 5.95 6.13 10.00 1.31 6.40 50.99 250 ppm A 1 20.5 40 60 19.75 60.75 90 250 ppm A 2 19.5 47 68.5 12.75 63 109 250 ppm A 3 30.5 52 56 17.75 56.5 121.5 250 ppm B 1 16.5 38 57 17.25 56.5 88.5 250 ppm B 2 23 48.5 32 17.5 51.5 48 250 ppm B 3 27 41 38 18.5 64 95 250 ppm C 1 19.5 40 52 14.75 43 90.5 250 ppm C 2 16.5 40 43.5 18.5 51 93.5 250 ppm C 3 17.5 37 52 14.5 41 100.5 250 ppm Mean 21.17 42.61 51.00 16.81 54.14 92.94 250 ppm Std Dev 4.84 5.22 11.38 2.29 8.25 19.97 500 ppm A 1 28.5 50.5 53 21.5 65.5 122 500 ppm A 2 21.5 49 48 16.75 70 97 500 ppm A 3 22 50.5 60 19.75 59.5 111.5 500 ppm B 1 27 60.5 65 16.75 72 98.5 500 ppm B 2 23.5 55 65.5 21 66 92.5 500 ppm B 3 24 51 55 20.75 56.75 101 500 ppm C 1 21.5 53 60 21.25 59.25 115 500 ppm C 2 20 52.5 54 20 59.5 99 500 ppm C 3 32 51 59.5 17.25 67.75 87.5 500 ppm Mean 24.44 52.56 57.78 19.44 64.03 102.67 500 ppm Std Dev 3.94 3.45 5.76 1.98 5.43 11.20 12